1600 John F. Kennedy Blvd.Ste 1800Philadelphia, PA 191032899

PEDIATRIC SURGERY ISBN: 978-0-323-07255-7Volume 1 9996085473Volume 2 9996085538

Copyright # 2012, 2006 by Saunders, an imprint of Elsevier Inc.

All rights reserved. No part of this publication may be reproduced or transmitted in any form or by anymeans, electronic or mechanical, including photocopying, recording, or any information storage andretrieval system, without permission in writing from the publisher. Details on how to seek permission,further information about the Publishers permissions policies and our arrangements with organizationssuch as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website:www.elsevier.com/permissions.

This book and the individual contributions contained in it are protected under copyright by the Publisher(other than as may be noted herein).

Notices

Knowledge and best practice in this field are constantly changing. As new research and experiencebroaden our understanding, changes in research methods, professional practices, or medical treatmentmay become necessary.

Practitioners and researchers must always rely on their own experience and knowledge in evaluating andusing any information, methods, compounds, or experiments described herein. In using such information ormethods they should be mindful of their own safety and the safety of others, including parties for whom theyhave a professional responsibility.

With respect to any drug or pharmaceutical products identified, readers are advised to check the mostcurrent information provided (i) on procedures featured or (ii) by the manufacturer of each product to beadministered, to verify the recommended dose or formula, the method and duration of administration,and contraindications. It is the responsibility of practitioners, relying on their own experience and knowledgeof their patients, to make diagnoses, to determine dosages and the best treatment for each individual patient,and to take all appropriate safety precautions.

To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors, assume anyliability for any injury and/or damage to persons or property as a matter of products liability, negligence orotherwise, or from any use or operation of any methods, products, instructions, or ideas contained in thematerial herein.

Library of Congress Cataloging-in-Publication Data

Pediatric surgery. 7th ed. / editor in chief, Arnold G. Coran ; associate editors, N.Scott Adzick . . . [et al.].

p. ; cm.Includes bibliographical references and index.ISBN 978-0-323-07255-7 (2 vol. set : hardcover : alk. paper)I. Coran, Arnold G., 1938- II. Adzick, N. Scott.[DNLM: 1. Surgical Procedures, Operative. 2. Child. 3. Infant. WO 925]

617.98dc23

2011045740

Editor: Judith FletcherDevelopmental Editor: Lisa BarnesPublishing Services Manager: Patricia TannianSenior Project Manager: Claire KramerDesigner: Ellen Zanolle

Printed in the United States of America

Last digit is the print number: 9 8 7 6 5 4 3 2 1

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

CHAPTER 74

Disordersof the UmbilicusRobert E. Cilley

History

Umbilical malformations have been depicted in art and sculp-ture since antiquity, but the developmental basis for theseabnormalities was not recognized until the late nineteenthcentury. Surgical textbooks, such as that by von Bergmannin 1904, clearly describe the embryology responsible for per-sistence of the vitellointestinal duct as a fistula, sinus, or cyst.1

The symptoms of fecal drainage (congenital umbilical anus)and prolapse of the intestine were well known. The surgeonwas advised to avoid pitfalls such as excision of an umbilicaltumor that exposed two intestinal lumens because it wouldindicate that the vitellointestinal remnant had been excisedin excess back to the ileum. An umbilical polyp represen-ting a persistent remnant of the duct was referred to as anenteroteratoma.

Surgicalmanagement has changed little in the past 100 years.Interestingly, then as now, granulomas of the umbilical cordwere treated by silver nitrate cauterization. The embryologicbasis of developmental abnormalities of the urachus was sim-ilarly recognized, and their surgical treatment was describedmuch as it is today. The natural history of spontaneous resolu-tion of most umbilical hernias was also understood at the endof the nineteenth century. External compression was often

recommended, and the importance of preservation of theappearance of the umbilicus rather than excision was empha-sized. Repair of umbilical abnormalities was recognized asformidable in small children, and little is known of the trueoperative morbidity and mortality in the hands of the surgicalpioneers who first attempted their correction.

The most complete work on the umbilicus is the classic textby Cullen, published in 1916.2 This encyclopedic work is stillthe most definitive work on the subject. Cullens curiosity wasoriginally stimulated by a case of cancer at the umbilicus, andit inspired him to explore the entire topic of umbilical pathol-ogy. He stated, The study of the umbilicus, which in thebeginning had seemed so unimportant, became so fascinatingthat I covered most of the literature on the subject.2

The vital functions of the umbilicus in utero and the struc-tures that pass through it in normal development contrast withits lack of physiologic importance after birth. Its psychologicimportance throughout life is attested to by individuals whohave endured surgical loss of their umbilicus. Pediatric sur-geons are the first to be consulted whenever there is anunusual finding of the umbilicus in newborns and olderchildren. Umbilical herniorrhaphy is among the more com-monly performed operations in childhood. In addition, theumbilicus serves as a portal of entry for most laparoscopic pro-cedures, and it may be used as an intestinal or urinary stomasite. Cannulation of its vessels, either in their native location ortransposed surgically, provides vascular access in neonates.The umbilicus is considered to be aesthetically important,3

and it may be an object of display and adornment. Exposureof the umbilicus is commonplace, as is the use of jewelry andpiercings to enhance its appearance.

Normal Embryology

The classic description of the formation of the umbilicusindicates that the abdominal wall forms by a combination oflateral infolding and ventral flexion of the disk-shaped trilami-nar embryo that begins in the fourth gestational week. How-ever, the actual growth of the embryo does not truly involvebending and folding of structures but rather representsdifferential growth of tissues. Initially, the amnion is locatedin a dorsal direction, whereas the yolk sac occupies a ventralposition. The embryo is attached to the chorion, the forerun-ner of the placenta, by a connecting stalk composed of extra-embryonic mesoderm in which the umbilical vessels developand into which the allantois grows (Fig. 74-1, A). The yolk sacmaintains its ventral position but is divided into intracoelomicand extracoelomic portions (Fig. 74-1, B). The intracoelomicportion, derived from the roof of the yolk sac, becomes theprimitive alimentary canal and maintains a connection withthe extracoelomic portion through the vitelline or omphalo-mesenteric duct. This connection is normally lost by the fifthto seventh week of gestation.2,4 Persistence of this connection,as a remnant of either the developing alimentary tract or theaccompanying vitelline vessels, accounts for some of theabnormalities described in this chapter.

Early in the third week of gestation, a diverticulum calledthe allantois forms from the posterior wall of the yolk sacand extends into the connecting stalk of the embryo(Fig. 74-1, A and B). The allantois serves as a reservoir forthe developing renal system in lower vertebrates but has no

961

A B

C DFIGURE 74-1 A, A 1.7-mm embryo (third week). The primitive gut is not yet separate from the yolk sac. The amniotic cavity can be seen dorsally.The umbilical vessels develop in the extraembryonic mesoderm and connect the embryo to the developing placenta. B, A 2.5-mm embryo (fourth week).Infolding and flexion of the embryo draw the amnion around the body. The omphalomesenteric duct is part of the developing umbilical cord. (From CullenTS: Embryology, Anatomy, and Diseases of the Umbilicus Together with Diseases of the Urachus. Philadelphia, WB Saunders, 1916.) C, A 5-mm embryo(fifth week) demonstrating a complete umbilical cord. The omphalomesenteric duct connection between the yolk sac and the alimentary tract is lostbetween the fifth and seventh weeks. D, A 45-mm embryo (10 weeks) viewed from inside. The intestines, which were extraembryonic coelomic (i.e., withinthe umbilical cord) between the sixth and tenth weeks, have returned to the peritoneal cavity.

962 PART VII ABDOMEN

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

known role in human development; it remains rudimentary asthe transitory extraembryonic portion of the urachus. As thedistal hindgut, or cloaca, partitions into the urogenital sinusventrally and the anorectal canal dorsally, the developing blad-der remains connected by the urachus to the allantois withinthe body stalk (see Fig. 74-1, D). The urachus is derivedwholly from the developing bladder andmay persist in variousforms, which accounts for the abnormalities described later.

As the embryo develops, the amnion is drawn around it tosurround the embryo and cover all the developing umbilicalcord structures including the allantois, umbilical vessels, vitel-line duct, and primitive mesenchymal tissue (Wharton jelly)(Fig. 74-1, C). During the period of rapid intestinal growthbetween the sixth and tenth weeks of gestation, the develop-ing midgut is extracoelomic. As the body wall continues todevelop, the intestines are incorporated into the coelomiccavity and intestinal rotation and fixation progress. The fibro-muscular umbilical ring continues to contract and is nearlyclosed by the time of birth (Fig. 74-1, D). Persistence of thefascial opening as an umbilical hernia occurs frequently andis commonly seen in premature infants. Unlike other abdom-inal wall defects, umbilical hernias tend to resolve withoutspecific treatment as a result of the ongoing development oftissues at the umbilical ring after birth. The fate of the struc-tures that relate to the development of the umbilicus is shownin Table 74-1.

Umbilicus at Birth

Modern obstetric practice uses plastic clamps that are placed afew centimeters from the umbilical skin during cord divisionat the time of delivery. Topical antimicrobials such as tripledye, bacitracin, silver sulfadiazine, povidone-iodine, chlor-hexidine, hexachlorophene, alcohol, salicylic sugar powder,green clay powder, silver-benzyl-peroxide powder, and 1%basic fuchsin may be applied to the cord after birth.5,6 Allthese agents are effective in reducing bacterial colonizationrates, and their use is recommended when adequate cord care

cannot be guaranteed. These agents may affect cord separationtime, some cause discoloration, and repeated use of iodine-containing antimicrobials may result in systemic absorptionof iodine and suppression of thyroid function. There is goodevidence that, in developed countries, dry cord care, withoutthe application of topical antibiotics, in association with rou-tine soap and water bathing and meticulous hand washingpractices is as effective as topical agents in reducing infection.7

However, a recent randomized prospective study demon-strated fewer cord-related complications in infants treatedwith chlorhexidine powder compared with standard drycord care.8 In the undeveloped world, antiseptic cord cleans-ing with chlorhexidine may significantly reduce neonatalmorbidity and mortality.9

Intestinal injurymay result from injudicious placement of anumbilical cord clampwhen an unrecognized small hernia of theumbilical cord (i.e., a small omphalocele) is present. Abdominalwall defects that relate to the umbilicus (i.e., gastroschisis andomphalocele) are covered in Chapter 75.

The normal time for separation of the umbilical cord afterbirth ranges from 3 days to 2 months.10 Antimicrobial treat-ment may prolong cord separation by decreasing leukocyteinfiltration. Delayed separation of the umbilical cord has beenassociated with heritable neutrophil mobility defects andwidespread infections that are often lethal.11 The abnormalneutrophils lack a membrane glycoprotein, which resultsin abnormal attachment, chemotaxis, and phagocytosis.10

Although persistence of umbilical cord attachment beyond3 weeks of age has been suggested to be a sign of such immu-nologic abnormalities, recent studies that have included morethan 600 newborns have demonstrated the range of normalnewborn cord separation to be broad (3 to 67 days), with amean of 14 to 15 days.10,12 In these studies, nearly 10% ofnormal newborns underwent cord separation after 3 weeksof age, thus indicating that delayed cord separation is not areliable indicator of immunologic disease. If prolonged cordseparation is associated with umbilical infection, leukocyteadhesion deficiency disorders should be suspected and animmunologic evaluation performed.6,13,14

TABLE 74-1

Fate of Structures Related to the Developing Umbilicus

Structure Fate Remnants, Pathologic Condition

Urachus (connects the bladderto the allantois)

Obliterates Median umbilical ligament, patent urachus,sinus, cyst

Omphalomesenteric duct(connects the midgut to theyolk sac)

Obliterates Meckel diverticulum, patent omphalomesenteric duct,sinus, cyst, bands, polyp

Omphalomesenteric arteries Most regress; fuse to form the celiac, superior mesenteric,and inferior umbilicus

Dominant arterymay accompanyMeckel diverticulum,fibrous band to the mesenteric arteries

Omphalomesenteric veins Plexus around the duodenum becomes the superiormesenteric and portal vein (contribution from boththe left and right vein)

Preduodenal portal vein if the ventral portionof the plexus persists

Umbilical arteries Obliterate after birth Medial or lateral umbilical ligaments*

Umbilical veins Right obliterates; left returns placental blood tothe inferior vena cava through the ductus venosus

Falciform ligament

*Atlases and anatomy texts variably refer to the obliterated umbilical arteries as themedial or lateral umbilical ligament.When called themedial umbilical ligaments,the epigastric vessels are called the lateral umbilical ligaments. When called the lateral ligaments, the epigastric vessels are referred to as the epigastric folds.

963CHAPTER 74 DISORDERS OF THE UMBILICUS

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

After separation of the cord, the umbilicus may have manyappearances. A normal umbilicus is characterized by a depres-sion in which may be found the mamelon (a central eminencethat contains the remnants of the solid portion of the umbilicalcord) and the cicatrix (dense scar where the intraembryonic andextraembryonic coelom were in continuity). The cushion is theslightly raised margin that surrounds the umbilical depression.Cullen described more than 60 normal configurations of theumbilicus.2

Umbilical Abnormalities

ACQUIRED

Umbilical Granuloma

After cord separation, a small mass of granulation tissue maydevelop at the base. These granulomas consist of true granu-lation tissue with fibroblasts and abundant capillaries; thegranulomas range in size from 1 mm to approximately 1 cm.The surface often has a pedunculated appearance. Umbilicalgranulomas may be treated by cauterization with one or moreapplications of silver nitrate until the area epithelializes. Alter-natively, the granuloma may be excised and silver nitrate orabsorbable hemostatic material applied.15 If the mass doesnot respond to cauterization, a true umbilical polyp or sinustract must be suspected (see later). Care must be taken withsilver nitrate application because burns and skin injury mayoccur.16

Umbilical Infections

Although modern perinatal practice has dramatically reducedthe incidence of omphalitis, infections of the umbilicus stilloccur with alarming morbidity and mortality, particularly inundeveloped countries.17 Rigorous asepsis, hand washing,and cord care (either dry cord care or topical antimicrobials)have reduced the incidence of umbilical infections to less than1% in hospitalized newborns.18 Before the institution ofsuch practices, the mortality rate for omphalitis was 65%.The primary pathogens implicated in these infections wereStaphylococcus aureus and Streptococcus pyogenes. Currently,gram-negative bacteria play an important role in the patho-genesis of umbilical infections. Severe infections are oftenpolymicrobial. Omphalitis may be manifested as a purulentumbilical discharge or periumbilical cellulitis. Delivery athome, low birth weight, use of umbilical catheters, and septicdelivery are risk factors. Tetanus infection occurs on rareoccasions. Intravenous antibiotic therapy is effective in erad-icating most infections. Omphalitis is a common problem indeveloping countries, where it accounts for more than aquarter of neonatal hospital admissions.19,20

Cellulitis may progress to fasciitis, and such progressionmay be subtle. Signs of necrotizing fasciitis include abdominaldistention, tachycardia, purpura, blistering, pyrexia, hypo-thermia, leukocytosis, and progression of cellulitis despiteantibiotic therapy. Bacteriologic cultures demonstrate polymi-crobial flora.21 Necrotizing fasciitis and umbilical gangrenemay be lethal and require immediate wide surgical debride-ment for patient survival.18,2227 Excision should be perfor-med immediately on recognition; all infected skin, fat, andfascia should be excised back to viable, bleeding abdomi-nal wall musculature. The umbilicus is obligatorily excised.

Excision of preperitoneal tissue including the umbilical vesselsand urachal remnant may be critically important to achieveeradication of the infectionbecause these tissues harbor invasivebacteria and may provide a route for the progressive spread ofinfection seen after less extensive surgical debridement.22 Thedefect may require a temporary prosthetic patch for closure,but ultimate fascial closure and umbilical reconstruction mayleave an acceptable appearance. Hyperbaric oxygen therapyhas been advocated as adjuvant therapy, but it is not of pro-ven benefit.26 The overall reported mortality associated withnecrotizing fasciitis in collected series is 81%.18,2227

Umbilical drainage resulting from chronic infection ofumbilical remnants such as umbilical artery remnants has alsobeen reported.28 Excision and debridement are curative.Omphalitis can result in necrosis and breakdown of theumbilical stump with spontaneous evisceration within thefirst 2 months of life and may be associated with portal venousthrombosis and subsequent extrahepatic portal hypertension.

CONGENITAL

Omphalomesenteric Remnants

Remnants of the vitelline or omphalomesenteric duct accountfor a wide variety of umbilical abnormalities that may requiresurgical correction.28a These remnants include fistulas, sinustracts, cysts, mucosal remnants, and congenital bands. Typi-cal variations of the pathologic varieties are illustrated inFigure 74-2, A to F.2,29,30

If the omphalomesenteric duct is patent from the terminalileum to the umbilicus, fecal umbilical drainage will be noted(Fig. 74-3, A). Although this event is dramatic to parents, theproblem is immediately recognizable on examination andparents may be reassured that prompt surgical correction iscurative. Prolapse of the proximal and distal ileum throughthe patent duct has a characteristic appearance. Although con-trast injections are of interest, they do not change the surgicalapproach (Fig. 74-3, B). Anatomically unusual conditionssuch as an unexpected origin of the omphalomesenteric ductfrom the appendix will be recognized at the time of operation(Fig. 74-4).31,32 Unless another, more serious medical con-dition exists, a patent omphalomesenteric duct should beexcised promptly. A mechanical intestinal preparation is notnecessary, although we customarily stop formula feeding;perioperative intravenous antibiotics are also given. The oper-ation may be performed through the umbilicus itself orthrough an incision below the umbilicus. Full explorationand identification of all umbilical structures including onevein, two arteries, and the urachal remnant are indicated.The omphalomesenteric duct is traced to the ileum anddivided. The ileum is closed, and care must be taken to controlany dominant vitelline vessels that may be present. After thefascia is closed, umbilicoplasty is performed.

Small duct remnants and sinuses may have less characteris-tic drainage. Injection of contrast material may be helpful indelineating the nature of the problem in these instances, butsurgical exploration remains the definitive diagnostic test. Itis important that a full exploration is performed and that allumbilical structures including the intraperitoneal undersurfaceof the umbilicus are visualized to identify and remove anybands attached to the small intestine. If a Meckel diverticulumis attached to an omphalomesenteric band discovered at explo-ration, it is excised. Cystic remnants of the omphalomesenteric

964 PART VII ABDOMEN

duct may become infected and cause acute symptoms, even inolder individuals. If an abscess has formed, it may require sur-gical drainage; excision of any remnant may be accomplishedat a later time. The omphalomesenteric duct or any remnantattachments between the abdominal wall and the intestine

maycause angulation, volvulus, orherniationof intestinal loops,thereby resulting in mechanical intestinal obstruction. Thenature of the obstruction will be discovered during laparotomy.

Rarely, spontaneous regression of a patent omphalo-mesenteric duct may occur.33,34 In one case the defect was

A B C

D E FFIGURE 74-2 Various omphalomesenteric duct remnants.A, Umbilical cyst containing intestinal tissue. B, Umbilical sinus with a band. C, Umbilical polypcovered with intestinal mucosa. D, Fibrous band containing a cyst. E, Meckel diverticulum. F, Patent omphalomesenteric duct. Other varieties andcombinations exist.

BA

FIGURE 74-3 A, This photo of a newborn demonstrates probe patency of an omphalomesenteric duct into the ileum. B, A radiograph with contrastmedium injected into a patent omphalomesenteric duct demonstrates filling of the small intestine. Studies of this sort are not usually necessary.

965CHAPTER 74 DISORDERS OF THE UMBILICUS

documented by a fistulogram shortly after birth, but it was notoperated on until the patient was 3 months of age. At thattime, only a Meckel diverticulum was found, but it had noconnection to the umbilicus, thus indicating that some regres-sion had occurred in the interim. The Meckel diverticulumand its treatment are discussed in Chapter 84.

Urachal Remnants

Various abnormalities of the urachus have beendescribed.2,35,36

The typical abnormalities are depicted in Figure 74-5. A patenturachus is associated with drainage of urine from the umbi-licus. Clear drainage from the umbilicus should always raisesuspicion of a patent urachus. Although the definitive anatomyis discovered during laparotomy, frank drainage of urine fromthe umbilicus requires an investigation of the urinary tractto look for bladder outlet obstruction in which the urachusis functioning as a relief valve (Fig. 74-6).37 Such conditionsare rare. A patent urachus may be approached either throughthe umbilicus or through an infraumbilical incision. It is

important to identify all the umbilical structures for a definitivediagnosis. The patent urachus is ligated and transected at thelevel of the bladder; broad-based connections are closed in twolayers with absorbable sutures. Excision of urachal remnantsusing laparoscopic techniques has been described.38,39

Urachal sinuses may give rise to umbilical drainage or bediscovered on examination. Urachal cysts most often causean infection manifested as a painful mass localized between

FIGURE 74-4 An unusual omphalomesenteric duct in continuity withthe appendix. Presentation was as a large umbilical polyp. Correctionwas performed through the umbilicus.

A B CFIGURE 74-5 Various urachal remnants. A, Patent urachus with communication between the bladder and umbilicus. B, Urachal sinus. C, Urachal cyst,which is usually associated with infection.

FIGURE 74-6 Radiograph with contrast medium injected into a patenturachus demonstrates filling of the bladder. (From Jona JZ: Umbilicalanomalies. In Raffensberger JG [ed]: Swensons Pediatric Surgery, 5th ed,Norwalk, Conn, Appleton & Lange, 1990. Used with permission.)

966 PART VII ABDOMEN

the umbilicus and the suprapubic area. Ultrasonography orcomputed tomography may be helpful to confirm the diagno-sis. Other unusual manifestations have been reported includ-ing a lateral mass.40 The urachus has also been described asexiting from the midline below the umbilicus.41,42 In addi-tion, a patent urachus may be one of the causes of a giant um-bilical cord in the newborn.43 When a urachal cyst becomesinfected and develops into an abscess, drainage of the acuteprocess is required. After the abscess is drained, completehealing may take place. It is unknown whether subsequentoperation to remove any residual cyst remnants is necessary.

Urachal remnants may cause complications later in life. Ab-normal epithelium including colonic, small intestine, andsquamous may be present in incidentally removed urachalremnants.44 The fate of these tissues is unknown, but manydifferent malignant tumors have been reported to originatefrom the urachus. A partial list of tumors in adults arising fromthe urachus is shown in Table 74-2. Pediatric tumors includ-ing rhabdomyosarcoma and neuroblastoma may originatefrom urachal remnants as well.45,46

Pain plus retraction of the umbilicus duringmicturition hasbeen described as a sign of a urachal anomaly.47,48 Resection ofthe urachal remnant is curative.

Diagnostic imaging including ultrasound, contrast injec-tions, computed tomography, and magnetic resonance imagingmay occasionally be helpful in diagnosing and treating umbil-ical abnormalities.49 An infant with umbilical discharge causedby both a persistent urachus and an omphalomesenteric ducthas been reported.50

Umbilical Dysmorphology

A single umbilical artery may occur in conjunction with manysyndromes and is associated with congenital abnormalities ina third of cases. Such abnormalities include trisomy 18 andrenal and cardiac anomalies. Children with dysmorphic fea-tures may have characteristic findings that aid in diagnosis.Minor abnormalities that lack medical significance can none-theless provide insight into the nature and timing of dysmor-phologic events that occur during development.51 Commonly,dermatoglyphics, hair patterning, auricular shape, and genitalconfiguration are part of such observations. Minor abnormal-ities of the configuration of the umbilicus may be useful in theclassification of dysmorphologic findings. For example, anumbilicus that is situated unusually high on the abdominalwall at the level of the lower rib cage and is flat and poorlyepithelialized indicates Robinow syndrome, which is alsocharacterized by a flat facial profile, mesomelic shortening,

and genital hypoplasia. If the umbilicus is broad and promi-nent with a large stalk and redundant periumbilical skin,Rieger syndrome should be suspected, especially if theseumbilical abnormalities occur in conjunction with goniodys-genesis and hypodontia. If the umbilicus is prominent witha button-like central portion in a deep longitudinally orien-ted ovoid depression or flat with radiating branches of thecicatrix, Aarskog syndrome, a condition classically character-ized by short stature, facial dysplasia, syndactyly, and genitalanomalies, is indicated.52

OTHER CONGENITAL AND ACQUIRED

PATHOLOGIC CONDITIONS

OF THE UMBILICUS

Suprapubic dermoid sinuses usually extend from the skin over-lying the pubis and pass over the superior surface of the bladderto the umbilicus alongside the urachus.53,54 The embryologicorigin of such a sinus tract remains unclear, although it maybe a variant of a dorsal urethral duplication.

Children with bladder and cloacal exstrophy may have anomphalocele or a low-set umbilicus incorporated into theupper portion of the open bladder plate, along with diastasisof the lower abdominal wall musculature and diastasis ofthe symphysis pubis.55 Variants of exstrophy include superiorvesicointestinal fissure, duplicate exstrophy, and pseudoexstro-phy, in which the bladder is intact and only the musculoskeletalabnormalities are present.

Numerous unusual protrusions have been described at theumbilicus. Ectopic pancreatic tissue including islets is bestexplained by the pluripotential nature of cells of the vitellineduct.56 Abnormal portions of liver connected to the mainlobes of the liver have been described and probably represententrapment by closure of the umbilical ring.57 A giant, 10-cmhamartoma originating from the umbilicus without intra-abdominal involvement has been excised without incident.58

The appendico-omphalic explanation of a fistula between theappendix and the umbilicus was noted earlier (Omphalome-senteric Remnants). Entrapment of the appendix in theumbilicus such as in a small omphalocele may also explainsome fistulas from the appendix to the umbilicus.59,60 Keloidformation has been observed after umbilical cord separation.61

A giant umbilical cord may contain urachal remnants andectatic vessels and may mask a small omphalocele. Care shouldbe exercised during application of the cord clampwhenever theappearance of the cord is abnormal.

The umbilicus may be affected by any disease of hair-bearing skin including dermatoses and infections. It may bethe site of ectopic tissue including endometriosis, as well asnumerous primary and metastatic tumors, in addition to thoseof urachal origin (see Table 74-2). Many acquired pathologicconditions of the umbilicus are summarized in Table 74-3.

Umbilical Piercing

Umbilical piercing is common and may present dilemmas inmanagement. Trauma surgeons should be familiar with theopening mechanisms of body piercings to facilitate radiologystudies and as needed for emergency procedures.62 Removalof the piercing device is not necessarily recommended ifinfection occurs.63 Local infections can be treated by warmcompresses and antibiotic ointment. If infection persists, oral

TABLE 74-2

Tumors Arising from the Urachus

Adenocarcinoma

Transitional cell carcinoma

Squamous cell carcinoma

Mucinous (cyst) adenocarcinoma

Malignant fibrous histiocytoma

Fibrosarcoma

Pleomorphic sarcoma

Yolk sac tumor

Inflammatory pseudotumor

Villous adenoma (premalignant)

967CHAPTER 74 DISORDERS OF THE UMBILICUS

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

antibiotics are prescribed. The site is cleansed with antibioticsoap, and the jewelry rotated and left in place to allow drain-age. Infections that require surgical drainage or debridementare rare. Navel piercing jewelry may be temporarily removedduring surgery while preserving the piercing sinus tract. Aplastic intravenous catheter is placed in the sinus when thepiercing is removed.64

UMBILICAL LINT

The origin of umbilical lint has been a subject of curiosity andspeculation. Experimental shaving on the periumbilical haireliminates lint formation. Lint collected from the umbilicusafter colored cotton shirts were worn by subjects with intactabdominal wall hair matched the color of the shirts indicatingthe source of the lint. Presumably umbilical lint collects asa direct result of the whorled umbilical hair acting on clothing-derived material. Hair encircles the umbilicus, and the keratinscales overlap with their bases pointing toward the hair follicle.This arrangement imposes direction on the random movementof the clothing lint that occurs when the material rubs backand forthacross theabdomenwithbodymovement.Theperium-bilical hairs act in a ratchet-like fashion to move the lint intothe depths of the umbilicus.

Umbilical Hernia

ANATOMY

At birth the umbilicus is surrounded by a dense fascial ringthat represents a defect in the linea alba. The umbilical open-ing is reinforced by strongly attached remnants of the umbil-ical arteries and urachus in an inferior direction and the moreweakly attached umbilical vein in a superior direction. A layerof fascia (Richet fascia) derived from the transversalis fasciasupports the base of the umbilicus. The peritoneum formsan intact undersurface of the umbilical ring, and skin overliesthe umbilicus after the cord has separated. When the support-ing fascia of the umbilical defect is weak or absent, a directhernia results.65 An umbilical hernia in children is sur-rounded by the dense fascia of the umbilical ring, throughwhich a peritoneal sac attached to the overlying skin pro-trudes. The umbilical ring continues to close over time andthe fascia of the umbilical defect strengthens, which accountsfor the spontaneous resolution of this defect in most children.

An indirect umbilical hernia has also been described inwhich the peritoneal contents herniate from a point immedi-ately superior to the umbilical ring. The hernia follows theumbilical canal along the umbilical vein, the linea alba in

TABLE 74-3

Acquired Conditions of the Umbilicus

Condition Comment Source

Dermatoses Seborrheic dermatitis, psoriasis, herpes gestationis, Fabry disease Powell, 1988a

Foreign body reactions Starch, talc, inserted objects Powell, 1988

Omphalith Concretion of keratinous and sebaceous material Powell, 1988

Pilonidal disease Related to hair-bearing sinus tracts Steck, 1965b

Sroujieh, 1989,c

Gupta, 1990d

Infections Bacterial, fungal, viral, parasitic Powell, 1988

Endometriosis Ectopic endometrial tissue Powell, 1988Franklin, 1990e

Benign tumors Nevi, pyogenic granuloma, inclusion cysts, hemangioma, dermatofibroma, neurofibroma,granular cell tumor, teratoma, desmoid tumor, lipoma

Powell, 1988

Malignant tumors, primary Melanoma, urachal adenocarcinoma, squamous cell carcinoma, basal cell carcinoma,sarcoma, leiomyosarcoma

Shetty, 1990f

Powell, 1988Cornil, 1967g

Malignant tumors, metastatic Stomach, pancreas, endometrium, ovary, cervix, colon, small intestine, gallbladder, lung,prostate, breast, unknown

Shetty, 1990

Enteric fistulas Originate from Crohn disease, perforated appendicitis, other such visceral perforationsas colon, gallbladder

Park 1991h

Veloso, 1989i

Burchell, 1989j

Psychiatric disorders Symbolic vagina Waltzer, 1974k

Miscellaneous disorders Perforation from a ventriculoperitoneal shunt; infections, dermatoses, and granulationtissue from piercing

Bryant, 1988l

Lena 1994m

aFrom Powell FC, Su WP: Dermatoses of the umbilicus. Int J Dermatol 1988;27:150-156.bSteck WD, Helwig EB: Umbilical granulomas, pilonidal disease and the urachus. Surg Gynecol Obstet 1965;120:1043-1057.cSroujieh AS, Dawoud A: Umbilical sepsis. Br J Surg 1989;76:687-688.dGupta S, Sikora S, Singh M, et al: Pilonidal disease of the umbilicusa report of two cases. Jpn J Surg 1990;20:590-592.eFranklin RR, Navarro C: Extragenital endometriosis. Prog Clin Biol Res 1990;323:289-295.fShetty MR: Metastatic tumors of the umbilicus: A review 1830-1989. J Surg Oncol 1990;45:212-215.gCornil C, Reynolds CT, Kickham CJ: Carcinoma of the urachus. J Urol 1967;98:93-95.hPark WH, Choi SO, Woo SK, et al: Appendicumbilical fistula as a sequela of perforated appendicitis. J Pediatr Surg 1991;26:1413-1415.iVeloso FT, Cardoso V, Fraga J, et al: Spontaneous umbilical fistula in Crohns disease. J Clin Gastroenterol 1989;11:197-200.jBurchell MC: Spontaneous umbilical fistula in Crohns disease. Report of a case. Dis Colon Rectum 1989;32:621-623.kWaltzer H: The umbilicus as vagina substitute. A clinical note. Psychoanal Q 1974;43:493-496.lBryant MS, Bremer AM, Tepas JJ 3rd, et al: Abdominal complications of ventriculoperitoneal shunts. Case reports and review of the literature. Am Surg 1988;54:50-55.mLena SM: Pierced navels are troublesome. CMAJ 1994;150:646-647.

968 PART VII ABDOMEN

an anterior direction, and a thin layer of preperitoneal fasciain a posterior direction.66 This form of herniation has beensuggested to cause proboscoid hernias in children; in thisdefect, the umbilical cicatrix is displaced progressively in aninferior direction as the hernia enlarges. This defect may alsobe responsible for umbilical hernias in some adults.

The umbilical hernia of childhood is distinguished froma hernia of the umbilical cord, in which there is a defectin the peritoneum, as well as an open fascial defect at theumbilicus. Intestines herniate into the substance of the umbil-ical cord itself and are covered only by amnion. A hernia of theumbilical cord is, in effect, a small omphalocele.

INCIDENCE AND NATURAL HISTORY

There is no doubt a molecular basis for umbilical ring clo-sure.67 Genetic heterogeneity accounts for the presence ofan open umbilical ring in some children at the time of birth,whereas in others, the ring is essentially closed at the time ofcord separation. Unlike inguinal and epigastric hernias, whichhave no real tendency to close after term, the umbilical ring isprogrammed to continue closure in many children for weeks,months, or years after birth.

Umbilical hernias in childhood occur with equal frequencyin boys and girls. Numerous reports document a high inci-dence in African and African American infants.6870 The umbil-ical ring is open throughout most of gestation but becomesprogressively smaller as gestation progresses. Most umbilicalhernias in infants are recognized after cord separation in thefirst few weeks of life, and almost all are noted by 6 monthsof age. Most undergo spontaneous closure during the first3 years of life. Umbilical defects are found in many prematureinfants after cord separation. Although umbilical hernias arecommonly found in low-birth-weight infants (75% of infantsweighing < 1500 g), most will resolve.71 The lack of accuratelongitudinal studies of children with umbilical defects doesnot allow definitive conclusions to be drawn about their naturalhistory.72Umbilical hernias with a small ring diameter (1.5 cm). The diameter ofthe umbilical defect is prognostically important, whereas thelength of the protrusion is not. Some umbilical hernias thatare present at 5 years of age will close spontaneously withoutan operation.73,74 The relationship between umbilical herniasthat become symptomatic later in life and childhood umbilicaldefects is unknown. The protruding portion of the hernia gen-erally remains unchanged while the fascial ring closes until it istoo small to admit any contents into the hernia sac. The herniathus tends to disappear abruptly.74 Umbilical hernias are com-monly observed in patients with Down syndrome, trisomy 18,trisomy 13, mucopolysaccharidoses, and congenital hypothy-roidism. Umbilical defects (hernia or omphalocele) are part ofthe Beckwith-Wiedemann syndrome. Incarceration of intestineor omentum, strangulation, perforation, evisceration, and painare rare events in the natural history of umbilical hernias inchildren. The most difficult task of the pediatric surgeon is toconvince the family that observation alone will be successfulin most cases and that an operation is not indicated for theirchild, especially in infancy. The large conspicuous skin-coveredhernia sac with its characteristic and unsettling appearance isoften associated with a small fascial defect. It may be helpfulto demonstrate the size of the actual fascial defect to the parent.

Uncorrected umbilical hernias can become symptomaticat any time in life. Rupture and evisceration are rare butcan occur.75,76 Incarceration is rare, but the small bowel ismost commonly affected when it does occur. Conditions thatincrease intra-abdominal pressure increase the likelihood ofcomplications. Repair of umbilical hernias in patients withascites is hazardous. Umbilical hernias may also becomesymptomatic during pregnancy, and if incarceration occurs,surgery is required. Unusual contents of umbilical herniasinclude uterine fibroids and endometrial elements.77,78

SURGICAL INDICATIONS

Although repair of childhood umbilical hernias has beenadvocated to prevent the complication of incarceration inadults, the relationship between the two events is unclear.79,80

Rare events such as incarceration requiring reduction, strangu-lation, perforation, and evisceration are absolute indications forsurgery. In the absence of these absolute indications, persistenceand appearance are relative indications for operative repair indeveloped countries. Infants with giant proboscoid hernias inwhom the umbilical ring does not narrow during serial obser-vations may be considered for repair in the first 2 years of life.Typical umbilical hernias should be observed at least until age 2.If there is no improvement in the size of the umbilical fascialring, consider repair. Ample evidence supports the decisionto postpone repair until later in childhood. Large defects(>1.5 cm) that persist past the age of 5 should be repaired.Evidence-based guidelines are lacking, and the decision maybe individualized on the basis of such considerations as familyhistory, parental desires, and local practices. The appearance of ahernia often drives families to insist that the hernia be repaired.In less developed parts of the world, it may be appropriate toactively observe umbilical hernias, with operation reservedfor those with complications such as incarceration.81,82

If the child has a tender umbilical mass, the hernia may bereduced by milking the air out of the incarcerated loop ofintestine and applying firm, steady pressure on the incarceratedmass. Admitting a patient for observation to rule out peritonitisand performing the operation the next day are appropriate. Ifthe incarceration resists reduction, an emergency procedure isrequired. In an infantwith an inguinal hernia and a concomitantumbilical hernia, the umbilical hernia should generally be leftalone because it will probably close spontaneously.

SURGICAL TECHNIQUE, RESULTS,

AND COMPLICATIONS

Procedures described for the repair of umbilical hernias inchildren range from multiple layers of closure after openingthe peritoneum to closed techniques in which the peritonealsac is inverted or treated like an inguinal hernia sac and ligatedwith sutures.83,84 Absorbable and nonabsorbable sutures havebeen advocated. The redundant skin of a large defect may beleft in place and improves in appearance over time. Some haveadvocated excision of the skin and reconstruction when alarge proboscoid hernia is present (see later). However, thefundamental technique of umbilical hernia repair has changedlittle since the 1953 description by Gross.85 Secure closure ofthe fascia, usually in a transverse fashion, and preservation ofthe appearance of the umbilicus are common to all repairs.Strapping and taping of the defects have been discredited.65,86

969CHAPTER 74 DISORDERS OF THE UMBILICUS

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Repair of an umbilical hernia is performed as an outpatientprocedure with the patient under general anesthesia. Localanesthesia may be infiltrated into the wound before or afterthe procedure, but paraumbilical infiltration avoids distor-tion of tissues by the anesthetic.87 Administration of localanesthesia before the incision conforms to the principles ofpreemptive analgesia. An infraumbilical skin crease incisionis made (Fig. 74-7). The incision may be hidden within theumbilicus itself. Subcutaneous dissection is performed tocircumscribe the sac. The sac is transected and may be dis-sected from the undersurface of the umbilical skin, but exten-sive and time-consuming dissection is unnecessary. Leaving asmall remnant of the peritoneal sac on the undersurface of theumbilical skin causes no complications. The sac may betrimmed to a strong fascial edge or simply folded inward toallow placement of interrupted absorbable sutures in a trans-verse orientation. To ensure accurate placement of sutures,they are tied after placement is complete. A second layer ofclosure is unnecessary. Inversion of the umbilical skin is main-tained with fine absorbable dermal suture between the under-side of the umbilicus and the midportion of the fascial closure.

The skin is closed with intradermal absorbable sutures andcovered with a small dressing. Some surgeons apply a pressuredressing; however, a recent randomized study showed nobenefit from application of a pressure dressing in standardchildhood umbilical hernia repair.88 Although infection pre-disposes to recurrence of the hernia, such complications arerare. Visceral injuries are possible but should not occur ifthe fascial edges are kept in view during the procedure.

Epigastric hernias can occur immediately adjacent to theumbilicus and may be difficult to distinguish from an umbil-ical hernia. Careful examination reveals a bulge at the uppermargin of the umbilicus or just above it. A supraumbilical in-cision permits repair of an adjacent epigastric hernia and si-multaneous repair if both umbilical and epigastric herniasare present.

Use of the Umbilicus

Cannulation of the umbilical arteries and umbilical vein iscommonly performed in sick neonates and provides a con-venient means for intravascular access and monitoring.

A

B

C

DE

FIGURE 74-7 Repair of an umbilical hernia. A, An infraumbilical, curvilinear incision is marked. B, The sac is encircled and opened. C, The fascia is closedtransversely. D, A tacking suture is placed between the undersurface of the umbilical skin and the fascia. E, Final result.

970 PART VII ABDOMEN

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Associated risks are related to infection, vascular thrombosis,and direct injury from catheters.89 There is insufficientoutcome-based evidence to either refute or support the useof prophylactic antibiotics when umbilical artery or venouscatheters are inserted in newborns.90,91 There is little evi-dence that heparin coating of the catheter or catheter materiallowers complication rates.92 The umbilicus is frequentlyused as the entry site for laparoscopic equipment. The centerof the umbilicus may be opened and the fascial ring probedand spread for access in infants, small children, and thosewith a shallow umbilicus. This technique leaves almost nodetectable incision. In patients with a deep umbilicus, a sep-arate infraumbilical incision may be preferable. The umbilicalport is most often used as the primary site for placement ofthe viewing camera. Closure of the fascial defect after removalof the port is necessary to reduce the risk for formation of ahernia. Single-port laparoscopic procedures using the umbili-cus as the only access site are gaining popularity in bothpediatric and adult surgery.93 The umbilicus has also beenused to mask the abdominal incision used for pyloromyotomyin cases of hypertrophic pyloric stenosis.94 This approachresults in an almost undetectable scar.

The umbilicus can also be used as a stoma site.95No studieshave compared the complication rate for intestinal stomasbrought out of the umbilicus with those brought out fromother locations in the abdominal wall; however, complicationsof umbilical stomas were reported by one study to be com-mon.96 After closure, the umbilicus is reconstructed and anearly normal appearance is achieved. We have used theumbilicus as a temporary ostomy site and have found it satis-factory. Though providing no physiologic benefit, it leaves thepatient with one less obvious incision site.

The umbilicus has also been used as an exit site for urinarydiversion. In premature infants, a temporary cutaneous vesi-costomy brought out of the umbilicus functions well and canbe closed with excellent cosmetic results.97 Intestinal con-duits for urinary diversion have also been brought out of theumbilicus.98

Reconstruction and Preservationof the Umbilicus

The umbilicus is aesthetically and psychologically important,and its abnormal appearance or absence may cause distress.Absence of the umbilicus may even be a source of griefand depression. The appearance of the umbilicus should beacceptable to the patient and family. A T-shaped or oval umbi-licus with a superior hood may be the most aestheticallyappealing configuration.3 A broad or protruding umbilicusmay be perceived to be less acceptable. One of the goals ofall umbilical surgical procedures is to maintain or restore asnormal an appearance as possible. Multiple techniques ofsurgical reconstruction or re-creation of the umbilicus havebeen described as noted later. Standard umbilical herniarepair produces minimal distortion of the umbilicus and gen-erally results in a satisfactory appearance. Omphalomesentericand urachal remnants can usually be excised through theumbilicus as noted earlier. After laparoscopy via the

umbilicus, if the umbilical skin is secured to the fascial clo-sure, a satisfactory umbilical depression is maintained. Patientsmay seek surgical correction for the perception of an unfavor-able appearance of the umbilicus such as protrusion. Umbilico-plasty to address the appearance of the umbilicus has become aniche within the discipline of plastic and reconstructive surgery.

UMBILICOPLASTY FOR GIANT HERNIAS

WITH REDUNDANT SKIN

When large hernias (giant proboscoid hernias) are repaired,the redundant skin results in an unnatural appearance. Someimprovement may occur with the passage of time, but a broad,flat, protruding configuration may persist. Reconstruction bya variety of techniques may improve the immediate and long-term appearance.99104 We have found the tripartite umbili-coplasty based on the technique described by Reyna andcolleagues to be satisfactory for immediate reconstruction ofgiant umbilical hernias.103 None of these described tech-niques has been widely adopted and shown to be superiorin long-term follow-up.

UMBILICOPLASTY FOR ABDOMINAL

WALL DEFECTS AND CREATION

OF A NEO-UMBILICUS

The umbilicus may be retained or reconstructed duringthe repair of abdominal wall abnormalities. The struc-tures of the umbilical cord may be incorporated into areconstruction of the umbilicus, or a neo-umbilicus maybe fashioned.105111

In gastroschisis and omphalocele, fascial repair may beperformed through the circular skin defect that remains afterthe umbilical structures have been excised. This is the case forboth primary and staged closures. The circular skin defectmay then be closed with an intradermal purse-string suturethat is incorporated into the middle of the fascial closure(Fig. 74-8, A).106 Even if the fascial defect is enlarged forthe application of a Silastic chimney, the lower portion ofthe defect can be closed in a similar circular fashion to createthe appearance of an umbilicus.105 Others have advocatedpreservation of the umbilicus in the repair of abdominal walldefects and leaving the umbilical remnants in place in conti-nuity with the skin closure.108,110,111 There is a trend towardpreservation of the native umbilicus in gastroschisis repair(Fig. 74-8, B).

The umbilicus is abnormally located in all children withbladder exstrophy and is often associated with a small ompha-locele defect. It may be transposed more cephalad at the timeof bladder closure to create a more normal appearance.112 Inchildren with prune-belly syndrome, the umbilicus may bepreserved on a vascularized pedicle and located appropriatelyafter the removal of excess skin.113

In some circumstances a new umbilicus must be construc-ted when it is absent as a result of previous surgical removal ortreatment of an abdominal wall defect. The normal locationfor the umbilicus is at the level of the iliac crests, overlyingthe third or fourth lumbar vertebrae. Umbilical reconstructionshould create a round or oval depression with steep walls that

971CHAPTER 74 DISORDERS OF THE UMBILICUS

is centrally fixed to the abdominal wall fascia (Fig. 74-9).Some umbilical reconstructions tend to flatten over time.Tubularized skin reconstructions may be more durable andmay also mimic the cushion or slightly raised area that sur-rounds the umbilical depression. Many techniques have beenproposed to reconstruct an absent umbilicus.106,109,114122

They vary considerably in their complexity, but none haveproved superior in long-term follow-up. Several techniqueshave been specifically described to reconstruct an absentumbilicus after exstrophy repair.112,123126

The complete reference list is available online at www.expertconsult.com.

FIGURE 74-9 Creation of a neo-umbilicus using a tubularized defattedskin pedicle in a patient with a giant omphalocele in conjunction with ab-dominal wall reconstruction.

A BFIGURE 74-8 Technique of umbilicoplasty after excision of the cord structures or when a procedure is performed through the umbilicus (e.g., surgicalrepair of gastroschisis or a small omphalocele, excision of an omphalomesenteric remnant through the umbilical ring, excision of a urachal remnantthrough the umbilicus). A, Child with gastroschisis after fascial closure. Placement of a circumferential purse-string dermal suture is shown. Note thatthe suture passes through the fascia. B, Retention of the umbilical cord after repair of gastroschisis.

972 PART VII ABDOMEN